JumpSystem

System Constructors

ModelingToolkit.JumpSystem — Type

struct JumpSystem{U<:RecursiveArrayTools.ArrayPartition} <: AbstractTimeDependentSystem

A system of jump processes.

Fields

eqs
The jumps of the system. Allowable types are ConstantRateJump, VariableRateJump, MassActionJump.

iv
The independent variable, usually time.
states
The dependent variables, representing the state of the system. Must not contain the independent variable.
ps
The parameters of the system. Must not contain the independent variable.
var_to_name
Array variables.
observed
name
The name of the system. . These are required to have unique names.
systems
The internal systems.
defaults
defaults: The default values to use when initial conditions and/or parameters are not supplied in ODEProblem.

connection_type
type: type of the system

Example

using ModelingToolkit

@parameters β γ 
@variables t S(t) I(t) R(t)
rate₁   = β*S*I
affect₁ = [S ~ S - 1, I ~ I + 1]
rate₂   = γ*I
affect₂ = [I ~ I - 1, R ~ R + 1]
j₁      = ConstantRateJump(rate₁,affect₁)
j₂      = ConstantRateJump(rate₂,affect₂)
j₃      = MassActionJump(2*β+γ, [R => 1], [S => 1, R => -1])
@named js      = JumpSystem([j₁,j₂,j₃], t, [S,I,R], [β,γ])

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Composition and Accessor Functions

get_eqs(sys) or equations(sys): The equations that define the jump system.
get_states(sys) or states(sys): The set of states in the jump system.
get_ps(sys) or parameters(sys): The parameters of the jump system.
get_iv(sys): The independent variable of the jump system.

Transformations

Missing docstring.

Missing docstring for structural_simplify. Check Documenter's build log for details.

Analyses

Problem Constructors

SciMLBase.DiscreteProblem — Type

function DiffEqBase.DiscreteProblem(sys::JumpSystem, u0map, tspan,
                                    parammap=DiffEqBase.NullParameters; kwargs...)

Generates a blank DiscreteProblem for a pure jump JumpSystem to utilize as its prob.prob. This is used in the case where there are no ODEs and no SDEs associated with the system.

Continuing the example from the JumpSystem definition:

using DiffEqBase, DiffEqJump
u₀map = [S => 999, I => 1, R => 0]
parammap = [β => .1/1000, γ => .01]
tspan = (0.0, 250.0)
dprob = DiscreteProblem(js, u₀map, tspan, parammap)

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DiscreteProblem(sys::DiscreteSystem, u0map, tspan) -> Any
DiscreteProblem(sys::DiscreteSystem, u0map, tspan, parammap; eval_module, eval_expression, kwargs...) -> Any

Generates an DiscreteProblem from an DiscreteSystem.

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DiffEqJump.JumpProblem — Type

function DiffEqBase.JumpProblem(js::JumpSystem, prob, aggregator; kwargs...)

Generates a JumpProblem from a JumpSystem.

Continuing the example from the DiscreteProblem definition:

jprob = JumpProblem(js, dprob, Direct())
sol = solve(jprob, SSAStepper())

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